With the exception of Michael Bloomberg, who has given over $1 billion to Johns Hopkins, perhaps no donor has done more for one school than Gordon Moore has done for the California Institute of Technology (Caltech). He and wife Betty have given the university over $700 million since 2001, with their latest big gift clocking in at $100 million. Here’s a closer look at their legacy, why they’ve given so much, and what’s to come.

Charitable giving for American higher ed is at an all-time high, with shrinking government budgets sending elite fundraising squads out to bring back billions from esteemed alumni. We’ve written extensively about this, and people don’t always react well to what this means for education in the country. The recent $400 million donation to Harvard in particular prompted widespread outrage (we stuck up for that gift…a little).

But the Moore-Caltech relationship in particular stands out, even in the current climate of endless zeros flying around.

A billionaire cofounder of Intel, Moore has played a huge role in establishing Caltech as arguably the best research school in the nation.

Since 2001, through their personal giving and their Gordon and Betty Moore Foundation, the Moores have committed more than $700 million to the school, along with another $250 million for a joint project between Caltech and the University of California to build the Thirty Meter Telescope in Hawaii. And despite their most recent huge unrestricted donation, there's no reason to believe they are done yet.

Aside from the sheer size of this gift, this philanthropic relationship is quite unique. Here are a few key observations:

Caltech is Tiny

The Pasadena school has a narrow, laser-like focus as an elite research institution. It’s small—with only 977 undergrads and 1,204 grad students. Just for perspective, Harvard has 10 times as many students, and University of Southern California 20 times more. This is not a big tent educational program.

In fact, Gordon Moore has said that its small size is one thing he likes the most about it. Moore earned his Ph.D. from the school in 1954, and believes its size fosters more interdisciplinary work because researchers aren't siloed in their departments. He once told Fortune, “At Caltech the biologists and the physicists have lunch together, which doesn’t happen elsewhere.”

That’s a perspective that will sound familiar to university fundraisers, because even at large schools seeking major financial support, work that crosses the boundaries of disciplines is constantly cited as a major selling point to donors.

The other interesting dynamic here is that, unlike larger schools, Caltech has far fewer alumni, and therefore fewer potential donors. It relies heavily on a small number of them, such as the Moores, plus federal grants, and donations from non-alumni who value its output.

Stanford economics professor Caroline Hoxby has compared highly selective universities to venture-capital firms, in that they invest in the best students, anticipating that some number of them will find tremendous financial success and return on the investment someday. That analogy seems particularly relevant here, with Caltech casting a much smaller net, but grooming entrepreneurial whales such as Gordon Moore.

Almost None of the Moores' Money Has Gone Toward Expansion

While school fundraising campaigns often go toward expansion—say, a new student union, a new satellite campus, a new department, a new squash facility, a virtual reality lab, a new training ground for a local corporation—none of that has been the case for the Moores' giving to Caltech.

When the couple made the $600 million commitment to the school in 2001, Caltech had an endowment of $1.5 billion, and a student body of 1,900. Today, its endowment is larger, but still just below $2 billion and enrollment has remained more or less flat. The president at the time said only a small portion of the 2001 donation would go toward the endowment, and the rest would go toward building existing programs to attract faculty and grants.

That hasn't been by the Moores' decree, however, as their non-foundation giving has been essentially unrestricted. Again, that’s an approach to major alumni giving we don’t really see very often. It’s more common for a large donor to want to put a stamp on some notable component of the school, or be part of a grand vision.

The Moores Have Backed Dozens of Research Programs

So what has Moore money made possible at Caltech? All sorts of things. For example, the foundation has made around 40 grants to the university reaching as high as $30 million, but often hovering in the $5 million to $10 million range. And aside from the huge investment in the Thirty Meter Telescope, giving really is varied, with emphases on neuroscience, cosmology, tectonics, and renewable energy.

Some of the grants have sprung from the foundation’s typically highly structured programs, such as support for work in marine microbiology and earthquake detection. As we've reported in the past, the Moore Foundation is fascinated by a range of scientific questions, emerging in the past decade as one of the largest private funders of basic research. In turn, Caltech is its favorite go-to shop for cutting-edge research.

The couple’s latest donation of $100 million adds an interesting twist, with the gift creating a permanent endowment to be used at Caltech’s complete discretion. In the announcement, Moore said, “We’d rather turn the job of deciding where to use resources over to Caltech than try to dictate it from outside.”The school decided to put it toward fellowships for graduate students to pursue creative interests, no doubt hoping to nurture their next Gordon Moore (and major donor).

There's More Where That Came From

Speaking of Gordon Moore, he is 86 years old. You have to wonder what’s next in terms of his philanthropy. The couple is among a generation of huge philanthropists, who have committed to giving most of their wealth away and are now getting up there in years.

The couple signed on to the Giving Pledge in 2012, but technically, they were on par to meet the goal of giving away at least half of their wealth when they first embarked on big-time philanthropy in 2001. The Moores endowed their foundation with the equivalent of around $5 billion, which at the time was about half of their wealth. The foundation will continue to channel funding to Caltech long after the Moores depart.

But today, Forbes still puts Gordon Moore’s net worth at $6 billion. I’m not going to split hairs about what “more than half” means, but you have to imagine we’re going to be seeing more of these infusions of cash to the couple’s causes. And that means big things for one little school in Pasadena.